Watching
film is an audio and visual. But many times sound is given less importance
than video. It is important to remember that sound is the second dimension
that brings your production alive.

Good
sound starts with a good microphone. The microphones on many DV video
cameras are decent, but they come with a few inherent limitations.
For one, the microphone is fixed to the camera so the microphone can
only be where the camera is. This problem is magnified when the subject
you are shooting is not close to the camera and there is a lot of
external noises. Another problem that results is camera noise. When
the audio level is low, the automatic gain control built into most
DV video cameras will compensate. Doing so brings out sounds you never
thought of: the sound of the tape drive, the automatic focus motor,
the zoom motor, or even your own breath. If you want professional
quality sound, you will have to buy an external mic

External Mics

There
are many types of mics, but the two we will be concerned with are:
lapel and shotgun microphones.

Lapel
Mics
Lapel microphones are very small microphones that clip onto the inside
of a persons' shirt. They are set up to only pick up sounds that are
within a certain radius of the mic. This helps isolate the sound to
make sure they only pick up your subject speaking, instead of a dog
barking in the distance.

Shotgun
Mics
Shotgun microphones look like a stick, and generally have higher overall
quality. They are used by pointing the microphone at the subject you
wish to record. Generally they are attached to a boom(a large stick)
then hung over you subjects out of frame.

Most
external mics require an external power source to power the mics.
Some have a battery, but most require a powered "pre-amp"
or "mixer" for the microphone to work.

You clip, you're
dead

Clipping
is when the sound exceeds a certain decibel level that either your
microphone or sound recorder can handle. Clipping isn't really an
issue when using the microphone that is built into most consumer level
DV video cameras because the Automatic Gain Control adjusts the gain
to compensate for low or high level noises. Examine the diagram and
notice how a Normal Sound Wave stays curvy. Now compare that to the
Sound Wave with Clipping. Notice how the clipped sound waves have
square tops, it looks as if the top curves were cut off.

When
sound is clipped, it has a very muffled scratchy sound that is not
very fun to listen to. To avoid clipping you must adjust the gain
control on your mixer. Careful not to adjust it too low or you will
end up with no sound at all, but if you adjust it too high everything
will sound scratchy and muffled because your sound is clipped. Also
be weary of cheap external microphones. Many cheap microphones can't
handle a very large decibel range, and can send a clipped signal to
your mixer or sound recording device.

There
is no way to fix a clipped sound. So it is always safer to adjust
your mixer to record sound at a lower level and then amplify the sound
in post production. But, if you adjust your mixer to record too low,
when you amplify the sound in post production you may hear the low
level electrical static sound mixed in with your source. Before you
start your shoot, practice with the levels to find the balance that
works best for you.